two columns resolve to the id '{id}', so the...

Warnings reference › columns.duplicate:*

Identifier

columns.duplicate:*

Raised by

The grid (core)

Since

1.4.0

What happened

Two column definitions ended up with the same id. The first is kept and the second refused, so the grid has one column where you declared two - everything the second definition configured is absent. A column's id defaults to its field, so this is usually two columns reading one field with different formatting.

The fix

Give each column an explicit id.

The smallest fix

columns: [{ id: 'amount', field: 'amount' }, { id: 'amountPct', field: 'amount', format: { style: 'percent' } }]

Reference

Covered in full at the API reference.